Expert says Jackson could not have caused own death by swallowing propofol

(CBS/AP) LOS ANGELES - An expert on propofol, the powerful anesthetic blamed for Michael Jackson's death, has told jurors there is no way the pop star could have caused his own death by swallowing the drug.

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Dr. Steven Shafer's testimony is a direct response to a report prepared by defense expert Dr. Paul White. White surmised that Jackson may have caused his own death by swallowing propofol.

Shafer is testifying Thursday on what is expected to be the final day of the prosecution's involuntary  manslaughter case against Dr. Conrad Murray.

Shafer said it's impossible for any propofol that's swallowed to enter the bloodstream, which is where coroner's officials found the drug after Jackson's June 2009 death.

The cardiologist's attorneys will cross-examine Shafer on Thursday.

Murray has pleaded not guilty. His attorneys are expected to begin presenting their case on Friday.

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